Continuous variable entanglement on a chip

TL;DR

This paper demonstrates the generation and characterization of continuous variable entangled states on a photonic chip, advancing integrated quantum photonics for scalable quantum information processing.

Contribution

It introduces an integrated photonic platform capable of producing and analyzing CV entanglement, enabling scalable and stable quantum information applications.

Findings

Successful on-chip generation of EPR entangled beams

Integrated squeezing and non-Gaussian operations demonstrated

Potential for universal quantum information processing on a chip

Abstract

Encoding quantum information in continuous variables (CV)---as the quadrature of electromagnetic fields---is a powerful approach to quantum information science and technology. CV entanglement---light beams in Einstein-Podolsky-Rosen (EPR) states---is a key resource for quantum information protocols; and enables hybridisation between CV and single photon discrete variable (DV) qubit systems. However, CV systems are currently limited by their implementation in free-space optical networks: increased complexity, low loss, high-precision alignment and stability, as well as hybridisation, demand an alternative approach. Here we show an integrated photonic implementation of the key capabilities for CV quantum technologies---generation and characterisation of EPR beams in a photonic chip. Combined with integrated squeezing and non-Gaussian operation, these results open the way to universal quantum information processing with light.